Port Node crypto to WebCrypto

[eligrey]

In order to reduce the worker script bundle size, we should look into porting our Node crypto usage to WebCrypto. This is a low priority task.

[bencmbrook]

This might be useful when we do
https://github.com/mozilla/send/blob/master/app/fileReceiver.js#L115
https://github.com/mozilla/send/blob/master/app/serviceWorker.js#L117

GitHub

mozilla/send

Simple, private file sharing from the makers of Firefox - mozilla/send

[bencmbrook]

I imagine there’s a ton of unused code in this dependency. We should first try tree shaking. It’s definitely not on since webpack is in development mode https://webpack.js.org/guides/tree-shaking/

[bencmbrook]

w3c/webcrypto#73

[bencmbrook]

I think this will be difficult because authentication checks are done under the hood for each call to crypto.subtle.decrypt, meaning we can't perform decryption on chunks (AFAIK).

https://github.com/jedisct1/libsodium.js has a web assembly that might have a similar perf gain.

[bencmbrook]

Investigate whether https://www.npmjs.com/package/libsodium-wrappers can handle whatwg streams

[bencmbrook]

https://webcrypto-streams.proposal.wintercg.org/